Headphone monitoring anomaly

[artbeat77]

I just picked up a Furman HA6AB, and am experiencing an odd monitoring situation.

When I hooked it up, I played a CD (digital out) through an Apogee Rosetta 200. That was sent to channels 1 & 2 of a Toft ATB32. Everything worked perfectly with the headphones connected to a Furman HR2 headphone box.

Today, during a session, I was monitoring tracks from the DAW. This is done through an Alesis HD24XR (optical in) from an RME HDSP9652, then line in (like the CD player) of the Toft ATB 32. For some reason, the headphones only worked in one ear (same HR2 setup). Of course, I had the "L-R" button of each channel depressed (just like the CD player).

I switched back to the CD player, and everything is fine.

I should mention that in both scenarios, the L and R LEDS on the front panel are illuminated.

Does anybody have any ideas why this setup is only sending to one ear of the headphones when monitoring from the DAW?

Thank you in advance,

Tony